I have an exercice consisted on:

X is a binary with raw data from the Austrian radar services.
Each radar station scans 16 vertical surfaces with a displacement of 1 km.

The file contains the reflectivity data for all locations where radar stations are available.
This is called the radar composite for Austria.

I have already codified the binary file following this:

Byte           Example                Description
0              1                      Format id (1)
1-7            31-Mar-1998 11:55      Date/Time
18-19                                 Number of rows (short int LSB first) (=NY)
20-21                                 Number of columns (=NX)
22                                    Number of 3D-levels (=L)
23-24                                 distance(m) between the 3D-levels (short int LSB first)
25                                    Number of quantisation levels (=N)
26-26+n*2-1                           quantisation levels (N * short int LSB first) in 1/10mm/h
X1-Y1                                 Pixels (NX*NY Bytes) from upper-left to down-right on the 1st 3D-Level
X2-Y2                                 Pixels (NX*NY Bytes) from upper-left to down-right on the 2nd 3D-Level
XL-YL                                 Pixels (NX*NY Bytes) from upper-left to down-right on the Lth 3D-Level

The problems asks:

creates a picture (PNG) with the highest value for each column (vertically)

Do you understand what does it ask based on the data I have? Value I assume comes from the Pixels value (which is codified in the range [1,14]) and map it into the quantisation_levels but I do not understand the question as a whole